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Unmanned aerial vehicles (UAVs) are currently under development for NASA missions, earth sciences, aeronautics, the military, and commercial applications. The design of an all electric power and propulsion system for small UAVs was the focus of a detailed study. Currently, many of these small vehicles are powered by primary (nonrechargeable) lithium-based batteries. While this type of battery is capable of satisfying some of the mission needs, a secondary (rechargeable) battery power supply system that can provide the same functionality as the current system at the same or lower system mass and volume is desired. A study of commercially available secondary battery cell technologies that could provide the desired performance characteristics was performed.

This paper describes the results of a Joint NASA/DoD Scenario-Based Systems Study conducted as part of the DoD Fixed-Wing Vehicle Technology Program. The study investigated both the impact and robustness of specific technology sets to a variety of airlift, bomber, and patrol aircraft concepts. The impacts of these technology sets were developed by measuring the changes in a set of measures of merit, which represented cost vs. capability metrics. The changes in the metrics were then evaluated within the context of a number of future “scenarios” to determine how robust these impacts would be across a variety of possible future conditions. A database was developed which allows the evaluation or ranking of the technology sets from a variety of perspectives.

This paper presents the results of a series of configuration studies conducted in connection with a NASA agility design study. The purpose of these in-house studies was to develop a parametric data base of configuration concepts and resulting mission performances for a variety of notional fighter/attack missions. This data base will then be used to assess the impact of the imposition of varying agility requirements on the configurations. Mission variations included range, payload, maximum dash Mach number, subsonic loiter time, and altitudes for air-to-air and air-to-ground missions. Ten design parameter variations were used including 5 “configuration” variables (Sw. AR, Taper Ratio, Thrust Vector Angle, Cvt) and 5 engine cycle variables (Design Thrust, Bypass ratio, OPR, T4, Throttle Ratio).